mb/google/rex: Add memory init

Add memory init with placeholder to fill in required memory
configuration parameters. DQ map and Rcomp can be auto probed by
the FSP-M hence, kept it as default.

BUG=b:224325352
TEST=util/abuild/abuild -p none -t google/rex -a -c max
Able to boot till FSP-M/MRC using MTL simics.

Signed-off-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
Signed-off-by: Subrata Banik <subratabanik@google.com>
Change-Id: I5baa87411c28a20602eb5a7077f00664ccab3ade
Reviewed-on: https://review.coreboot.org/c/coreboot/+/64850
Reviewed-by: Tarun Tuli <taruntuli@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/google/rex/Kconfig

@@ -10,6 +10,7 @@ config BOARD_GOOGLE_BASEBOARD_REX
 	select EC_GOOGLE_CHROMEEC
 	select EC_GOOGLE_CHROMEEC_ESPI
 	select MAINBOARD_HAS_CHROMEOS
+	select MEMORY_SOLDERDOWN
 	select SOC_INTEL_METEORLAKE
 	select SYSTEM_TYPE_LAPTOP
 
@@ -44,4 +45,12 @@ config VARIANT_DIR
 	string
 	default "rex0" if BOARD_GOOGLE_REX0
 
+config DIMM_SPD_SIZE
+	default 512
+
+config MEMORY_SOLDERDOWN
+	def_bool n
+	select CHROMEOS_DRAM_PART_NUMBER_IN_CBI if CHROMEOS
+	select HAVE_SPD_IN_CBFS
+
 endif # BOARD_GOOGLE_REX_COMMON

src/mainboard/google/rex/Makefile.inc

@@ -16,6 +16,8 @@ BASEBOARD_DIR:=$(call strip_quotes,$(CONFIG_BASEBOARD_DIR))
 
 subdirs-y += variants/baseboard/$(BASEBOARD_DIR)
 subdirs-y += variants/$(VARIANT_DIR)
+subdirs-y += variants/$(VARIANT_DIR)/memory
+subdirs-$(CONFIG_HAVE_SPD_IN_CBFS) += spd
 
 CPPFLAGS_common += -I$(src)/mainboard/$(MAINBOARDDIR)/variants/baseboard/include
 CPPFLAGS_common += -I$(src)/mainboard/$(MAINBOARDDIR)/variants/baseboard/$(BASEBOARD_DIR)/include

src/mainboard/google/rex/romstage.c

@@ -3,12 +3,21 @@
 #include <baseboard/variants.h>
 #include <fsp/api.h>
 #include <soc/romstage.h>
+#include <string.h>
 
 void mainboard_memory_init_params(FSPM_UPD *memupd)
 {
 	const struct pad_config *pads;
 	size_t pads_num;
+	const struct mb_cfg *mem_config = variant_memory_params();
+	bool half_populated = variant_is_half_populated();
+	struct mem_spd spd_info;
 
 	pads = variant_romstage_gpio_table(&pads_num);
 	gpio_configure_pads(pads, pads_num);
+
+	memset(&spd_info, 0, sizeof(spd_info));
+	variant_get_spd_info(&spd_info);
+
+	memcfg_init(memupd, mem_config, &spd_info, half_populated);
 }

src/mainboard/google/rex/spd/Makefile.inc

@@ -0,0 +1,6 @@
+## SPDX-License-Identifier: GPL-2.0-or-later
+##
+
+ifneq ($(SPD_SOURCES),)
+LIB_SPD_DEPS := $(SPD_SOURCES)
+endif

src/mainboard/google/rex/variants/baseboard/include/baseboard/variants.h

@@ -4,6 +4,7 @@
 #define __BASEBOARD_VARIANTS_H__
 
 #include <soc/gpio.h>
+#include <soc/meminit.h>
 #include <stdint.h>
 #include <vendorcode/google/chromeos/chromeos.h>
 
@@ -15,4 +16,9 @@ const struct pad_config *variant_gpio_table(size_t *num);
 const struct pad_config *variant_early_gpio_table(size_t *num);
 const struct pad_config *variant_romstage_gpio_table(size_t *num);
 
+const struct mb_cfg *variant_memory_params(void);
+void variant_get_spd_info(struct mem_spd *spd_info);
+int variant_memory_sku(void);
+bool variant_is_half_populated(void);
+
 #endif /*__BASEBOARD_VARIANTS_H__ */

src/mainboard/google/rex/variants/baseboard/rex/Makefile.inc

@@ -1,5 +1,6 @@
 bootblock-y += gpio.c
 
 romstage-y += gpio.c
+romstage-y += memory.c
 
 ramstage-y += gpio.c

src/mainboard/google/rex/variants/baseboard/rex/memory.c

@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include <baseboard/gpio.h>
+#include <baseboard/variants.h>
+#include <gpio.h>
+
+static const struct mb_cfg baseboard_memcfg = {
+	.type = MEM_TYPE_LP5X,
+	/* TODO: Add Memory configuration */
+	.ect = 1, /* Enable Early Command Training */
+};
+
+const struct mb_cfg *__weak variant_memory_params(void)
+{
+	return &baseboard_memcfg;
+}
+
+int __weak variant_memory_sku(void)
+{
+	return 0;
+}
+
+bool __weak variant_is_half_populated(void)
+{
+	return 0;
+}
+
+void __weak variant_get_spd_info(struct mem_spd *spd_info)
+{
+	spd_info->topo = MEM_TOPO_MEMORY_DOWN;
+	spd_info->cbfs_index = variant_memory_sku();
+}

src/mainboard/google/rex/variants/rex0/memory/Makefile.inc

@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+# This is an auto-generated file. Do not edit!!
+
+SPD_SOURCES =
+SPD_SOURCES += spd/lp5/set-0/spd-empty.hex      # ID = 0(0b0000)

src/mainboard/google/rex/variants/rex0/memory/dram_id.generated.txt

@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+# This is an auto-generated file. Do not edit!!
+
+DRAM Part Name                 ID to assign
+empty			        0 (0000)

src/mainboard/google/rex/variants/rex0/memory/mem_parts_used.txt

@@ -0,0 +1 @@
+empty